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Electrical System
Add-On Electrical Equipment
Notice:Don't add anything electrical to your
vehicle unless you check with your dealer ®rst.
Some electrical equipment can damage your vehicle
and the damage wouldn't be covered by your
warranty. Some add-on electrical equipment can
keep other components from working as they
should.
Your vehicle has an air bag system. Before attempting
to add anything electrical to your vehicle, see
Servicing Your Air Bag-Equipped Vehicle on page 1-59.
Headlamps
The headlamp wiring is protected by four fuses. An
electrical overload will cause a lamp to go on and off. If
this happens, have your headlamp wiring checked
right away.
Windshield Wiper Fuses
The windshield wiper motor is protected by a circuit
breaker and a fuse. If the motor overheats due to heavy
snow or ice, the wiper will stop until the motor cools.
If the overload is caused by some electrical problem, be
sure to get it ®xed.
Power Windows and Other Power
Options
Circuit breakers protect the power windows and other
power accessories. When the current load is too heavy,
the circuit breaker opens and closes, protecting the
circuit until the problem is ®xed or goes away.
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Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses and circuit
breakers. This greatly reduces the chance of ®res
caused by electrical problems.
Look at the silver-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure you
replace a bad fuse with a new one of the identical
size and rating.
If you ever have a problem on the road and don't have
a spare fuse, you can borrow one that has the same
amperage. Just pick some feature of your vehicle
that you can get along without Ð like the radio or
cigarette lighterÐ and use its fuse, if it is the correct
amperage. Replace it as soon as you can.
Engine Compartment Fuse Block
The fuse block is located under the hood in the engine
compartment on the driver's side of the vehicle. See
Engine Compartment Overview on page 5-12for more
information on location.
Remove the primary cover by pressing the two locking
tabs. Remove the secondary cover by snapping off
while lifting. To reinstall the fuse panel cover, reverse
the sequence.
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Fuses Usage
1Electrically-Controlled Air
Suspension
2Passenger's Side High-Beam
Headlamp
3Passenger's Side Low-Beam
Headlamp
4 Back-Up-Trailer Lamps
5Driver's Side High-Beam
Headlamp
6Driver's Side Low-Beam
Headlamp
7 Wash
8 Automatic Transfer Case
9 Windshield Wipers
10 Powertrain Control Module B
11 Fog Lamps
12 Stop Lamp
13 Cigarette Lighter
14 Ignition Coils
15 Air Suspension Ride
16 TBD-Ignition 1
17 CrankFuses Usage
18 Air Bag
19 Electric Brake
20 Cooling Fan
21 Horn
22 Ignition E
23 Electronic Throttle Control
24Instrument Panel Cluster, Driver
Information Center
25Automatic Shift Lock Control
System
26 Engine 1
27 Back-Up
28 Powertrain Control Module 1
29 Oxygen Sensor
30 Air Conditioning
31 Truck Body Controller
32 Trailer
33 Anti-Lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
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Fuses Usage
50 Passenger's Side Trailer Turn
51 Driver's Side Trailer Turn
52 Hazard Flashers
Relays Usage
37 Blank
38 Rear Window Washer
39 Fog Lamps
40 Horn
41 Fuel Pump
42 Windshield Wipers/WasherFuses Usage
43 High-Beam Headlamp
44 Air Conditioning
45 Cooling Fan
46 Headlamp Driver Module
47 Starter
Miscellaneous Usage
48 Instrument Panel Battery
49 Blank
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Fuses Usage
1Electrically-Controlled Air
Suspension
2Passenger's Side High-Beam
Headlamp
3Passenger's Side Low-Beam
Headlamp
4 Back-Up-Trailer Lamps
5Driver's Side High-Beam
Headlamp
6Driver's Side Low-Beam
Headlamp
7 Wash
8 Automatic Transfer Case
9 Windshield Wipers
10 Powertrain Control Module B
11 Fog Lamps
12 Stop Lamp
13 Cigarette Lighter
14 Ignition Coils
15 Canister Vent
16 TBD - Ignition 1
17 Crank
18 Air BagFuses Usage
19 Electric Brake
20 Cooling Fan
21 Horn
22 Ignition E
23 Electronic Throttle Control
24Instrument Panel Cluster, Driver
Information Center
25Automatic Shift Lock Control
System
26 Engine 1
27 Back-Up
28 Powertrain Control Module 1
30 Air Conditioning
31 Truck Body Controller
32 Trailer
33 Anti-Lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
50 Passenger's Side Trailer Turn
51 Driver's Side Trailer Turn
52 Hazard Flashers
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Fuses Usage
53 Oxygen Sensor Bank A
54 Oxygen Sensor Bank B
55 Injector Bank A
56 Injector Bank B
Relays Usage
37 Headlamp Washer
38 Rear Window Washer
39 Fog Lamps
40 Horn
41 Fuel Pump
42 Windshield Wipers/Washer
43 High-Beam Headlamp
44 Air Conditioning
45 Cooling Fan
46 Headlamp Driver Module
47 Starter
58 Ignition 1
Miscellaneous Usage
48 Instrument Panel BatteryRear Underseat Fuse Block
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Fuses Usage
01 Right Door Control Module
02 Left Door Control Module
03 Liftgate Module 2
04 Truck Body Controller 3
05 Rear Fog Lamps
06Liftgate Module/Driver Seat
Module
07 Truck Body Controller 2
08 Power Seats
09 Blank
10 Driver Door Module
11 Ampli®er
12 Passenger Door Module
13 Rear Climate Controls
14 Left Rear Parking Lamps
15 Auxiliary Power 2
16Vehicle Center High-Mounted
Stop Lamp
17 Right Rear Parking Lamps
18 Locks
19 Blank
20 Sunroof
21 Lock
23 Blank
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Fuses Usage
24 Unlock
25 Blank
26 Blank
27 OH Battery/OnStar
žSystem
29 RainsenseŸ Wipers
30 Parking Lamps
31Truck Body Controller 4 Cruise
Control
32 Truck Body Controller 5
33 Front Wipers
34 Vehicle Stop
35 Blank
36Heat Ventilation Air
Conditioning B
37 Front Parking Lamps
38 Left Turn Signal
Fuses Usage
39Heat Ventilation Air
Conditioning 1
40 Truck Body Controller 4
41 Radio
42 Trailer Park
43 Right Turn Signal
44 Heat Ventilation Air Conditioning
45 Rear Fog Lamps
46 Auxiliary Power 1
47 Ignition 0
48 Four-Wheel Drive
49 Blank
50 Truck Body Controller Ignition
51 Brakes
52 Truck Body Controller Run
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